Flexible Outputs from Square Wave Driver - This circuit can produce an output signal ranging from DC to 100KHz. it can source a voltage ranging from 1v to 30v. it can sink a voltage ranging from zero volts to –30v. it can drive up to 200ma of current and can even be switched to a floating tristate . . . Hobby Circuit designed by David Johnson P.E.-July, 2000

Gated 125Khz Oscillator - This circuit is uses a NAND gate as an inverter. The gate allows the oscillator to be gated on and off. Again, the values shown set the frequency at 125KHz but can be changed to produce other frequencies . . . Hobby Circuit designed by Dave Johnson P.E.-March, 2002

Gated Crystal Oscillator with Very Low Power - The circuit gates the output of a continuously operating 32KHz crystal oscillator to the input of a C-MOS buffer when clock pulses are needed. The technique gets around the problem of a slow starting crystal oscillator by keeping the oscillator going and switching on a transistor power stage only as needed . . . Hobby Circuit designed by David A. Johnson P.E.-June, 2000

Generate Short Delayed Pulse - This circuit generates a short 10ms pulse 15 minutes after a “start” pushbutton switch is activated . . . Hobby Circuit designed by David Johnson P.E.-October, 2005

Highly Stable Lower Power Oscillator - This circuit works much like the classic 555 timer, but draws only about 1.5 microamps from a 3 volt battery. it is highly stable under varying temperature and supply voltages. . . . Hobby Circuit designed by David A. Johnson P.E.-May, 2000

Few Extra Components Stabilize Oscillator - 02/15/96 EDN Design Ideas: The circuit beneath the dashed line in Figure 1 is the well-known Wien-bridge oscillator. The lamp is a common tungsten incandescent bulb. its resistance forms a substantial part of the gain-setting network. For the oscillator to function properly, the increase in lamp resistance accruing from the ac signal must bring the open-loop __ Circuit Design by Israel Schleicher, Green Spin Bakersfield, CA

FleaPower Oscillator Consumes only 1 µA - 05/21/98 Design ideas - (Multiple circuits listed, scroll to find this one) A simple way to make an oscillator is to use a resistor, a capacitor, and a Schmitt trigger (Figure 1a]. However, this circuit uses several tens of microamperes because of the voltage transitions at the Schmitt trigger's input. The CMOS
device consumes almost no power when the input is either high or low. Whenever the input voltage is at an intermediate __ Circuit Design by Yongping Xia, Teldata Inc, Los Angeles, CA

Flexible Outputs from Square Wave Driver - This circuit can produce an output signal ranging from DC to 100KHz. it can source a voltage ranging from 1v to 30v. it can sink a voltage ranging from zero volts to –30v. it can drive up to 200ma of current and can even be switched to a floating tristate . . . Hobby Circuit designed by David Johnson P.E.-July, 2000

Form Positive Pulses from Negative Pulses - 07/14/11 EDN Design Ideas: Create positive pulses even when negative pulses vary in amplitude. The circuit in this Design idea converts negative pulses to positive pulses. Although that task may seem simple, the negative pulses have amplitudes of −5 to −2V. The positive pulses also need different pulse widths, depending on the application, and the negative pulses are trapezoidal. The pulses must travel over a long-distance transmission line to a control device. Several circuits solve the problem, depending on the amplitude and shape of the pulses. __ Circuit Design by Vladimir Rentyuk, Zaporozhye, Ukraine

Four Frequencies Generator - During development, testing and maintenance of digital and analogue electronic circuits and embedded systems, there is a need for TTL and CMOS
signals produced by stable frequency sources. These sources are...__ Electronics Projects for You

Function generator based on 8038PCD - Built around a single 8038 waveform generator IC , this circuit produces sine, square or triangle waves from 20Hz to 200kHz in four switched ranges. There are both high and low level outputs which may be adjusted with the level control. This project makesa useful addition to any hobbyists workbench as well __ Designed by Andy Collison

Gated 125Khz Oscillator - This circuit is uses a NAND gate as an inverter. The gate allows the oscillator to be gated on and off. Again, the values shown set the frequency at 125KHz but can be changed to produce other frequencies . . . Hobby Circuit designed by Dave Johnson P.E.-March, 2002

Gated Crystal Oscillator with Very Low Power - The circuit gates the output of a continuously operating 32KHz crystal oscillator to the input of a C-MOS buffer when clock pulses are needed. The technique gets around the problem of a slow starting crystal oscillator by keeping the oscillator going and switching on a transistor power stage only as needed . . . Hobby Circuit designed by David A. Johnson P.E.-June, 2000

Gated Oscillator Emulates a Flip-Flop - 03/16/95 EDN Design Ideas: The gated oscillator in Fig 1 holds its existing state when disabled rather than being forced high or low-a singular property. Further, you can generate an output at one-half the input frequency if you choose R1 and C so that the oscillator changes state just once when its input goes high. This configuration eliminates a flip-flop. __ Circuit Design by Einar Abell, ADA Instruments, Three Rivers, CA

Gated RC Phaseshift Oscillator - Scroll down. The last circuit is a simpler R-C phase shift oscillator, but this is one with a difference: it is gated, i. e. it can be turned on by an input signal. Earth the input and the oscillator stops, connect it to 5v and the oscillator starts. The oscillator will always start in the same fashion, with a positive edge __ Designed by Richard Torrens

Generate an Analog Signal with a µC - 10/22/98 EDN Design Ideas: Applications requiring D/A conversion abound, including dual-tone generation, motor-speed control, and offset-voltage generation for a sensor or for battery charging. Most designers believe the D/A converter must be either an integrated module in a µC or an external component; however, __ Circuit Design by Thomas Schmidt, Microchip Technology, Chandler, AZ

Generate Short Delayed Pulse - This circuit generates a short 10ms pulse 15 minutes after a “start” pushbutton switch is activated . . . Hobby Circuit designed by David Johnson P.E.-October, 2005

Generate stabilized PWM signals - 08/17/00 EDN Design Ideas: A standard technique for generating analog voltages using µCs is to use a PWM output and filter the signal with a simple RC filter (Figure 1). The voltage of the PWM signal is directly proportional to the µC's supply voltage, so __ Circuit Design by Martin Ossmann, FH, Aachen, Germany

Generate Swept Sine/Cosine Waveforms with Two Filters - 06/23/11 EDN Design Ideas: Phase difference holds between 89° and 90°. Demodulators, directional circuits, and other electronics applications often need two sine waves with a 90° difference in phase—a sine wave and its cosine wave. Engineers typically use analog filters to create the phase shift. This approach, however, offers a limited frequency range. Using the circuit in Figure 1, you can make a swept sine/cosine pair at frequencies of less than 1 Hz to 25 kHz. __ Circuit Design by John R Ambrose, Mixed Signal Integration, San Jose, CA

Generating-5 Volts from a 9 Volt Battery - This is a basic 555 squarewave oscillator used to produce a 1 Khz tone from an 8 ohm speaker. in the circuit on the left, the speaker is isolated from the oscillator by the NPN medium power transistor which also provides more current than can be obtained directly from the 555 (limit = 200 mA). A small capacitor is used at the transistor __ Designed by Bill Bowden

Generator has independent pulse width, frequency - 11/11/99 - EDN Design Ideas: A common circuit in electronics is the square-wave, astable multivibrator (one-shot) , which is useful for various purposes, such as timing circuits and audible alarms. The most common way to generate the desired square wave is to use the inexpensive 555 timer. The need sometimes arises for a square wave with fixed frequency but variable pulse width or vice versa. __ Circuit Design by Davinder Oberoi

Gnat-power sawtooth oscillator works on Low supply voltages - 05/15/13 EDN Design Ideas: Making basic analog circuit functions that operate from a low-voltage battery supply can be tricky. Lack of headroom and the need to minimize supply and leakage currents are usually the biggest challenges. __ Circuit Design by Bruce D Moore, Consulting Analog Enginee

Harmonic Oscillator - Here is an easy-build high-performance VHF (or UHF?) local oscillator. There are no PCB foil drawings to play with and no coils to wind. There are two 90mm long copper wire inductors needed, but the good news is, you don't have to wind them. The first unit makes an excellent 10mW (+10dBm) exciter to drive a VHF power amplifier __ Designed by Harry Lythall-SM0VPO

High Speed Data Conversion - The Signal/Waveform Generator creates sine, square, triangle, and noise signals in a repeated or triggered fashion to help design, test, or troubleshoot an electrical device. The system block diagram presented above includes on board signal synthesis and control via a DSP and microcontroller, respectively. A General Purpose interface Bus (GPiB) and RS-232 port are typical communication options for signal generators but higher speed interface options are available through Local-Area Network (LAN) , Universal Serial Bus (USB) , and Peripheral Component interconnects (PCi) __ Designed by Texas Instruments App Notes, 2-Oct-00

Highly Stable Lower Power Oscillator - This circuit works much like the classic 555 timer, but draws only about 1.5 microamps from a 3 volt battery. it is highly stable under varying temperature and supply voltages. . . . Hobby Circuit designed by David A. Johnson P.E.-May, 2000

High-Speed Pulse Generator Has Programmable Levels - 12/31/69 EDN Design Ideas: Lilliputian dimensions associated with the submicron geometries of most digital and many analog processes result in much faster circuit operation. As ICs speed up, the rise and fall times of most pulse and function generators, which are typically 5 nsec, become inadequate for measuring time intervals lower than 20 nsec. You can overcome this limitation with analog comparators or advanced CMOS
logic gates, which create faster digital edges. __ Circuit Design by John Guy, Maxim Integrated Products, Sunnyvale, CA

High-Speed Pulse Modulator Retains Signal Envelope - 06-Aug-09 EDN Design Ideas: Modulated signals have the ac components they need to pass through transformers. - The circuit in Figure 1 enables you to convert an arbitrary, relatively slowly varying voltage waveform to a new waveform in which the instantaneous values of the original waveform alternate with positive and negative signs. The new waveform retains information about the original waveform, . __ Circuit Design by MariĂˇn Stofka, Slovak University of Technology, Bratislava, Slovakia

High-Voltage DC Generator - Voltage, by definition, is the electrical pressure that causes current to flow through a conductor. When that pressure is sufficiently high, a high voltage is produced. But how do we define high-voltage? is 100, 1000, or 10, 000 volts considered high voltage? When compared to 10 volts, they all can be considered high voltage __ Designed by Tony van Roon VA3AVR

Injection-Lock a Wien-Bridge Oscillator - 10/31/12 EDN Design Ideas: A low-distortion Meacham-bulb-stabilized Wien-bridge oscillator is used to acquire the FFT of a pure sinusoid of about 5 kHz. I recently had the opportunity to investigate a new micropower 6-MHz LTC6255 op amp driving a 12-bit, 250k sample/sec LTC2361 ADC. I wanted to acquire the FFT of a pure sinusoid of about 5 kHz. The problem is that getting the FFT of a pure sinusoid requires, well, a pure sinusoid. Most programmable signal generators, however, have fairly poor noise and distortion performance, not to mention digital “hash” floors, compared with dedicated op amps and good ADCs. You can’t measure 90-dB distortion and noise using sources that are “60 dB-ish. ” __ Circuit Design by Glen Brisebois, Applications Engineer, Signal Conditioning group at Linear Technology